CLASS PISCES. 575 



Aluteres, Cuv., 



Have the body elongated, covered with small and 

 crowded grains, scarcely sensible to the view ; a single 

 spine to the first dorsal ; and, what constitutes their 

 peculiar character, the pelvis entirely concealed under 

 the skin, and not forming the spiny projection observ- 

 able in the other balistes f . 



Triacanthus, Cuv., 



Are distinguished from all the other balistes, because 

 they have sorts of ventrals, sustained each by a single 

 large spinous ray, and adherent to a pelvis not salient. 

 Their first dorsal, after one very large spine, has three 

 or four small ones. Their skin is furnished with 

 small crowded scales ; their tail is more elongated 

 than in the other subgenera. 



But a single species is known, from the Indian 

 Ocean 2 . 



Ostracion, L., (Vulg. Trunk-Jish.) 



Have, in lieu of scales, osseous and regular compart- 

 ments soldered into a sort of inflexible cuirass, 



1 Bal. monoceros, L., Catesb. 19 ; the monoceros of Bl., which is 

 different, 147. Bal. Icevis, Bl. 414. Acaramucu, Marcgr. 163, still 

 different from the preceding three. Bal. Kleinii, Klein. Misc. III. 

 pi. Hi. f. 2. Al. cryptacanthus, C, Renard, II. part of pi. xlii. 

 f. 284. 



2 Bal. biaculealus, Bl. 148. 2. We shall have numerous species 

 of all these subgenera to describe in our History of Fishes. 



